Investigation of the binding affinity gases on porous adsorbents are important for establishing understanding of effective carbon dioxide adsorption and design target specific sorbents for capturing hazardous gases for environmental protection and fuel upgrading. A Density Functional Theory (DFT) study that highlights the impact of covalent organic polymer (COP) design has been conducted to explain the molecular and electronic structure, investigate the interaction sites and elucidate the experimental findings on carbon dioxide (CO2) and nitrogen (N2) sorption on these porous structures. DFT calculations were used to infer the details of the type and the strength of the polymer – gas interaction modes at various interaction sites as well as to quantify short‐range interactions between the polymer – gas via topological characteristics analysis of intermolecular forces. Results obtained in this study were used to shed light on CO2 and N2 affinity of the studied polymer structures; interpretations regarding to the macroscopic behaviors were discussed and conclusions were attained on the characteristics of the adsorption type and mechanism.